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Analyzing nonpoint source water pollution problems
1997
Favero, Philip
Himalayan microbial diversity
1997
Sati, S. C. | Saxena, J. (Jitendra) | Dubey, R. C.
The interactions between sediments and water
1997
Evans, R. Douglas | Wisniewski, Joe | Wisniewski, Jan R.
Water pollution IV
1997
Rajar, R (Rudi) | Brebbia, C. A.
Direct aqueous derivation and gas chromatographic analysis of halogenated lower carboxylates in environmental samples
1997
Ozawa, H. (Nagano-ken. Research Inst. for Health and Pollution (Japan))
Analytical method for hydrophilic polar environmental pollutants was studied. Among these pollutants, the halogenated lower carboxylates were the target compounds of this investigation. A novel but simple derivatization method necessary for sample preparation for instrumental analysis was developed. The new derivatization method for the carboxylates is not a conventional chemical reaction in non-aqueous solvent following isolation from the environmental samples but rather, a direct aqueous reaction ; direct conversion of the carboxylates to amides using a carbodiimide in dilute aqueous solution. Halogenoanilines were selectively used with dicyclohexylcarbodiimide (DCC) under acidic conditions at room temperature to form the anilide derivatives. Moreover, this reaction proceeds while mixing the sample water, DCC, a halogenoaniline, and small volume of extracting solvent. Thus, for the first time, simultaneous derivatization of the carboxylates and extraction of the products into solvent was achieved. Based on the results, simple and practical determination methods by gas chromatography were developed for traces of these carboxylates in environmental samples and the proposed methods were applied to some real samples. Such analytical derivatization methods for carboxylates are useful and noteworthy because they can form C-N bonds in aqueous media under mild conditions with carbodiimides and N atoms of amino and other compounds.
Показать больше [+] Меньше [-]Survey of river water acidification in Nagano prefecture [Japan]
1997
Miyajima, I. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Katsuno, T. | Takeda, Y. | Shiozawa, K.
Best management practices for pollution prevention in the textile industry | Best management practices for pollution prevention in the textile industry
1997
Runoff of pesticides from paddy fields after aerial spray
1997
Sasaki, K. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Terasawa, J.
Contact treatment of secondary treated domestic waste water using charcoal bed
1997
Kohno, Y. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Suzuki, T. | Yokokawa, T. | Terashima, T.
A survey on the actual use of natural additives
1997
Watanabe, T. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Miyagawa, A. | Nakamura, K.
